skb allocation / cosumption tracer - Add consumption tracepoint
This patch adds a tracepoint to skb_copy_datagram_iovec, which is called each
time a userspace process copies a frame from a socket receive queue to a user
space buffer. It allows us to hook in and examine each sk_buff that the system
receives on a per-socket bases, and can be use to compile a list of which skb's
were received by which processes.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
include/trace/events/skb.h | 20 ++++++++++++++++++++
net/core/datagram.c | 3 +++
2 files changed, 23 insertions(+)
Signed-off-by: David S. Miller <davem@davemloft.net>
dev_queue_xmit enqueue's a skb and calls qdisc_run which
dequeue's the skb and xmits it. In most cases, the skb that
is enqueue'd is the same one that is dequeue'd (unless the
queue gets stopped or multiple cpu's write to the same queue
and ends in a race with qdisc_run). For default qdiscs, we
can remove the redundant enqueue/dequeue and simply xmit the
skb since the default qdisc is work-conserving.
The patch uses a new flag - TCQ_F_CAN_BYPASS to identify the
default fast queue. The controversial part of the patch is
incrementing qlen when a skb is requeued - this is to avoid
checks like the second line below:
+ } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) &&
>> !q->gso_skb &&
+ !test_and_set_bit(__QDISC_STATE_RUNNING, &q->state)) {
Results of a 2 hour testing for multiple netperf sessions (1,
2, 4, 8, 12 sessions on a 4 cpu system-X). The BW numbers are
aggregate Mb/s across iterations tested with this version on
System-X boxes with Chelsio 10gbps cards:
----------------------------------
Size | ORG BW NEW BW |
----------------------------------
128K | 156964 159381 |
256K | 158650 162042 |
----------------------------------
Changes from ver1:
1. Move sch_direct_xmit declaration from sch_generic.h to
pkt_sched.h
2. Update qdisc basic statistics for direct xmit path.
3. Set qlen to zero in qdisc_reset.
4. Changed some function names to more meaningful ones.
Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This sockopt goes in line with SO_TYPE and SO_PROTOCOL. It makes it
possible for userspace programs to pass around file descriptors — I
am referring to arguments-to-functions, but it may even work for the
fd passing over UNIX sockets — without needing to also pass the
auxiliary information (PF_INET6/IPPROTO_TCP).
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Similar to SO_TYPE returning the socket type, SO_PROTOCOL allows to
retrieve the protocol used with a given socket.
I am not quite sure why we have that-many copies of socket.h, and why
the values are not the same on all arches either, but for where hex
numbers dominate, I use 0x1029 for SO_PROTOCOL as that seems to be
the next free unused number across a bunch of operating systems, or
so Google results make me want to believe. SO_PROTOCOL for others
just uses the next free Linux number, 38.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
String literals are constant, and usually, we can also tag the array
of pointers const too, moving it to the .rodata section.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Current neigh_periodic_timer() function is fired by timer IRQ, and
scans one hash bucket each round (very litle work in fact)
As we are supposed to scan whole hash table in 15 seconds, this means
neigh_periodic_timer() can be fired very often. (depending on the number
of concurrent hash entries we stored in this table)
Converting this to a workqueue permits scanning whole table, minimizing
icache pollution, and firing this work every 15 seconds, independantly
of hash table size.
This 15 seconds delay is not a hard number, as work is a deferrable one.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is a path when an assetion in dev_unicast_sync() appears.
igmp6_group_added -> dev_mc_add -> __dev_set_rx_mode ->
-> vlan_dev_set_rx_mode -> dev_unicast_sync
Therefore we cannot protect this list with rtnl. This patch restores the
original protecting this list with spinlock.
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Tested-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: David S. Miller <davem@davemloft.net>
memcpy() should take into account size of pointers,
not only number of pointers to copy.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to make cfg80211/nl80211 aware of network namespaces,
we have to do the following things:
* del_virtual_intf method takes an interface index rather
than a netdev pointer - simply change this
* nl80211 uses init_net a lot, it changes to use the sender's
network namespace
* scan requests use the interface index, hold a netdev pointer
and reference instead
* we want a wiphy and its associated virtual interfaces to be
in one netns together, so
- we need to be able to change ns for a given interface, so
export dev_change_net_namespace()
- for each virtual interface set the NETIF_F_NETNS_LOCAL
flag, and clear that flag only when the wiphy changes ns,
to disallow breaking this invariant
* when a network namespace goes away, we need to reparent the
wiphy to init_net
* cfg80211 users that support creating virtual interfaces must
create them in the wiphy's namespace, currently this affects
only mac80211
The end result is that you can now switch an entire wiphy into
a different network namespace with the new command
iw phy#<idx> set netns <pid>
and all virtual interfaces will follow (or the operation fails).
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This helps avoid error messages with ethtool -k on devices that
don't provide device specific routines.
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
------------------------------------------------------------------
Signed-off-by: David S. Miller <davem@davemloft.net>
mac80211 required this due to the master netdev, but now
it can put all information into skb->cb and this can go.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
For mac80211, with the master netdev removal, we need to be
able to sync a multicast address list onto another list that
is not tracked within a netdev, so we need access to the
functions doing that.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
I guess it should be -EINVAL rather than EINVAL. I have not checked
when the bug came in. Perhaps a candidate for -stable?
Signed-off-by: Rémi Denis-Courmont <remi.denis-courmont@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit e912b1142b
(net: sk_prot_alloc() should not blindly overwrite memory)
took care of not zeroing whole new socket at allocation time.
sock_copy() is another spot where we should be very careful.
We should not set refcnt to a non null value, until
we are sure other fields are correctly setup, or
a lockless reader could catch this socket by mistake,
while not fully (re)initialized.
This patch puts sk_node & sk_refcnt to the very beginning
of struct sock to ease sock_copy() & sk_prot_alloc() job.
We add appropriate smp_wmb() before sk_refcnt initializations
to match our RCU requirements (changes to sock keys should
be committed to memory before sk_refcnt setting)
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Rename lookup_neigh_params to lookup_neigh_parms as the struct is named
neigh_parms and all other functions dealing with the struct carry
neigh_parms in their names.
Signed-off-by: Tobias Klauser <klto@zhaw.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
The function get_net_ns_by_pid(), to get a network
namespace from a pid_t, will be required in cfg80211
as well. Therefore, let's move it to net_namespace.c
and export it. We can't make it a static inline in
the !NETNS case because it needs to verify that the
given pid even exists (and return -ESRCH).
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
All we need to take care of is using proper RCU list
add/del primitives and inserting a synchronize_rcu()
at one place to make sure the exit notifiers are run
after everybody has stopped iterating the list.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some sockets use SLAB_DESTROY_BY_RCU, and our RCU code correctness
depends on sk->sk_nulls_node.next being always valid. A NULL
value is not allowed as it might fault a lockless reader.
Current sk_prot_alloc() implementation doesnt respect this hypothesis,
calling kmem_cache_alloc() with __GFP_ZERO. Just call memset() around
the forbidden field.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Adding memory barrier after the poll_wait function, paired with
receive callbacks. Adding fuctions sock_poll_wait and sk_has_sleeper
to wrap the memory barrier.
Without the memory barrier, following race can happen.
The race fires, when following code paths meet, and the tp->rcv_nxt
and __add_wait_queue updates stay in CPU caches.
CPU1 CPU2
sys_select receive packet
... ...
__add_wait_queue update tp->rcv_nxt
... ...
tp->rcv_nxt check sock_def_readable
... {
schedule ...
if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
wake_up_interruptible(sk->sk_sleep)
...
}
If there was no cache the code would work ok, since the wait_queue and
rcv_nxt are opposit to each other.
Meaning that once tp->rcv_nxt is updated by CPU2, the CPU1 either already
passed the tp->rcv_nxt check and sleeps, or will get the new value for
tp->rcv_nxt and will return with new data mask.
In both cases the process (CPU1) is being added to the wait queue, so the
waitqueue_active (CPU2) call cannot miss and will wake up CPU1.
The bad case is when the __add_wait_queue changes done by CPU1 stay in its
cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1 will then
endup calling schedule and sleep forever if there are no more data on the
socket.
Calls to poll_wait in following modules were ommited:
net/bluetooth/af_bluetooth.c
net/irda/af_irda.c
net/irda/irnet/irnet_ppp.c
net/mac80211/rc80211_pid_debugfs.c
net/phonet/socket.c
net/rds/af_rds.c
net/rfkill/core.c
net/sunrpc/cache.c
net/sunrpc/rpc_pipe.c
net/tipc/socket.c
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Using early netconsole and gianfar driver this error pops up:
netconsole: timeout waiting for carrier
It appears that net/core/netpoll.c:netpoll_setup() is using
cond_resched() in a loop waiting for a carrier.
The thing is that cond_resched() is a no-op when system_state !=
SYSTEM_RUNNING, and so drivers/net/phy/phy.c's state_queue is never
scheduled, therefore link detection doesn't work.
I belive that the main problem is in cond_resched()[1], but despite
how the cond_resched() story ends, it might be a good idea to call
msleep(1) instead of cond_resched(), as suggested by Andrew Morton.
[1] http://lkml.org/lkml/2009/7/7/463
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some PHYs require longer timeouts for carrier detection, and
auto-negotiation process may take indefinite amount of time.
It may be inconvenient to force longer timeouts for sane PHYs,
so let's introduce a kernel command line option.
Since we're using module_param(), the option also can be
changed in runtime.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch converts the remaining occurences of raw return values to their
symbolic counterparts in ndo_start_xmit() functions that were missed by the
previous automatic conversion.
Additionally code that assumed the symbolic value of NETDEV_TX_OK to be zero
is changed to explicitly use NETDEV_TX_OK.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
When NAPI is disabled while we're in net_rx_action, we end up
calling __napi_complete without flushing GRO packets. This is
a bug as it would cause the GRO packets to linger, of course it
also literally BUGs to catch error like this :)
This patch changes it to napi_complete, with the obligatory IRQ
reenabling. This should be safe because we've only just disabled
IRQs and it does not materially affect the test conditions in
between.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6:
bnx2: Fix the behavior of ethtool when ONBOOT=no
qla3xxx: Don't sleep while holding lock.
qla3xxx: Give the PHY time to come out of reset.
ipv4 routing: Ensure that route cache entries are usable and reclaimable with caching is off
net: Move rx skb_orphan call to where needed
ipv6: Use correct data types for ICMPv6 type and code
net: let KS8842 driver depend on HAS_IOMEM
can: let SJA1000 driver depend on HAS_IOMEM
netxen: fix firmware init handshake
netxen: fix build with without CONFIG_PM
netfilter: xt_rateest: fix comparison with self
netfilter: xt_quota: fix incomplete initialization
netfilter: nf_log: fix direct userspace memory access in proc handler
netfilter: fix some sparse endianess warnings
netfilter: nf_conntrack: fix conntrack lookup race
netfilter: nf_conntrack: fix confirmation race condition
netfilter: nf_conntrack: death_by_timeout() fix
In order to get the tun driver to account packets, we need to be
able to receive packets with destructors set. To be on the safe
side, I added an skb_orphan call for all protocols by default since
some of them (IP in particular) cannot handle receiving packets
destructors properly.
Now it seems that at least one protocol (CAN) expects to be able
to pass skb->sk through the rx path without getting clobbered.
So this patch attempts to fix this properly by moving the skb_orphan
call to where it's actually needed. In particular, I've added it
to skb_set_owner_[rw] which is what most users of skb->destructor
call.
This is actually an improvement for tun too since it means that
we only give back the amount charged to the socket when the skb
is passed to another socket that will also be charged accordingly.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Tested-by: Oliver Hartkopp <olver@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (55 commits)
netxen: fix tx ring accounting
netxen: fix detection of cut-thru firmware mode
forcedeth: fix dma api mismatches
atm: sk_wmem_alloc initial value is one
net: correct off-by-one write allocations reports
via-velocity : fix no link detection on boot
Net / e100: Fix suspend of devices that cannot be power managed
TI DaVinci EMAC : Fix rmmod error
net: group address list and its count
ipv4: Fix fib_trie rebalancing, part 2
pkt_sched: Update drops stats in act_police
sky2: version 1.23
sky2: add GRO support
sky2: skb recycling
sky2: reduce default transmit ring
sky2: receive counter update
sky2: fix shutdown synchronization
sky2: PCI irq issues
sky2: more receive shutdown
sky2: turn off pause during shutdown
...
Manually fix trivial conflict in net/core/skbuff.c due to kmemcheck
This patch is inspired by patch recently posted by Johannes Berg. Basically what
my patch does is to group list and a count of addresses into newly introduced
structure netdev_hw_addr_list. This brings us two benefits:
1) struct net_device becames a bit nicer.
2) in the future there will be a possibility to operate with lists independently
on netdevices (with exporting right functions).
I wanted to introduce this patch before I'll post a multicast lists conversion.
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
drivers/net/bnx2.c | 4 +-
drivers/net/e1000/e1000_main.c | 4 +-
drivers/net/ixgbe/ixgbe_main.c | 6 +-
drivers/net/mv643xx_eth.c | 2 +-
drivers/net/niu.c | 4 +-
drivers/net/virtio_net.c | 10 ++--
drivers/s390/net/qeth_l2_main.c | 2 +-
include/linux/netdevice.h | 17 +++--
net/core/dev.c | 130 ++++++++++++++++++--------------------
9 files changed, 89 insertions(+), 90 deletions(-)
Signed-off-by: David S. Miller <davem@davemloft.net>
The skb mac_header field is sometimes NULL (or ~0u) as a sentinel
value. The places where skb is expanded add an offset which would
change this flag into an invalid pointer (or offset).
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Looking at the crash in log_martians(), one suspect is that the check for
mac header being set is not correct. The value of mac_header defaults to
0 on allocation, therefore skb_mac_header_was_set will always be true on
platforms using NET_SKBUFF_USES_OFFSET.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch changes FDB entry check for ATM LANE bridge integration.
There's no point in holding a FDB entry around SKB building.
br_fdb_get()/br_fdb_put() pair are changed into single br_fdb_test_addr()
hook that checks if the addr has FDB entry pointing to other port
to the one the request arrived on.
FDB entry refcounting is removed as it's not used anywhere else.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit b00055aacd " [NET] core: add
RFC2863 operstate" defined new interface flag values. Its
documentation specified that these flags could be accessed from user
space via SIOCGIFFLAGS. However, this does not work because the new
flags do not fit in that ioctl's argument width.
Change the documentation to match the code's behavior. Also change
the source to explicitly show the truncation. This _should_ have no
effect on executable code, and did not with gcc 4.2.4 generating x86
code.
A new ioctl could be defined to return all interface flags to user
space. However, since this has been broken for three years with no
one complaining, there doesn't seem much need. They are still
accessible via netlink.
Reported-by: "Fredrik Arnerup" <fredrik.arnerup@edgeware.tv>
Signed-off-by: John Dykstra <john.dykstra1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current code errors out the INCOMPLETE neigh entry skb queue only from
the timer if maximum probes have been attempted and there has been no reply.
This also causes the transtion to FAILED state.
However, the neigh entry can be also updated via Netlink to inform that the
address is unavailable. Currently, neigh_update() just stops the timers and
leaves the pending skb's unreleased. This results that the clean up code in
the timer callback is never called, preventing also proper garbage collection.
This fixes neigh_update() to process the pending skb queue immediately if
INCOMPLETE -> FAILED state transtion occurs due to a Netlink request.
Signed-off-by: Timo Teras <timo.teras@iki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
One of the problem with sock memory accounting is it uses
a pair of sock_hold()/sock_put() for each transmitted packet.
This slows down bidirectional flows because the receive path
also needs to take a refcount on socket and might use a different
cpu than transmit path or transmit completion path. So these
two atomic operations also trigger cache line bounces.
We can see this in tx or tx/rx workloads (media gateways for example),
where sock_wfree() can be in top five functions in profiles.
We use this sock_hold()/sock_put() so that sock freeing
is delayed until all tx packets are completed.
As we also update sk_wmem_alloc, we could offset sk_wmem_alloc
by one unit at init time, until sk_free() is called.
Once sk_free() is called, we atomic_dec_and_test(sk_wmem_alloc)
to decrement initial offset and atomicaly check if any packets
are in flight.
skb_set_owner_w() doesnt call sock_hold() anymore
sock_wfree() doesnt call sock_put() anymore, but check if sk_wmem_alloc
reached 0 to perform the final freeing.
Drawback is that a skb->truesize error could lead to unfreeable sockets, or
even worse, prematurely calling __sk_free() on a live socket.
Nice speedups on SMP. tbench for example, going from 2691 MB/s to 2711 MB/s
on my 8 cpu dev machine, even if tbench was not really hitting sk_refcnt
contention point. 5 % speedup on a UDP transmit workload (depends
on number of flows), lowering TX completion cpu usage.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (244 commits)
Revert "x86, bts: reenable ptrace branch trace support"
tracing: do not translate event helper macros in print format
ftrace/documentation: fix typo in function grapher name
tracing/events: convert block trace points to TRACE_EVENT(), fix !CONFIG_BLOCK
tracing: add protection around module events unload
tracing: add trace_seq_vprint interface
tracing: fix the block trace points print size
tracing/events: convert block trace points to TRACE_EVENT()
ring-buffer: fix ret in rb_add_time_stamp
ring-buffer: pass in lockdep class key for reader_lock
tracing: add annotation to what type of stack trace is recorded
tracing: fix multiple use of __print_flags and __print_symbolic
tracing/events: fix output format of user stack
tracing/events: fix output format of kernel stack
tracing/trace_stack: fix the number of entries in the header
ring-buffer: discard timestamps that are at the start of the buffer
ring-buffer: try to discard unneeded timestamps
ring-buffer: fix bug in ring_buffer_discard_commit
ftrace: do not profile functions when disabled
tracing: make trace pipe recognize latency format flag
...
In order to handle powersave frames properly we had needed
to pass these out to the device queues again, and introduce
the skb->requeue bit. This, however, also has unnecessary
overhead by needing to 'clean up' already tried frames, and
this clean-up code is also buggy when software encryption
is used.
Instead of sending the frames via the master netdev queue
again, simply put them into the pending queue. This also
fixes a problem where frames for that particular station
could be reordered when some were still on the software
queues and older ones are re-injected into the software
queue after them.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
IEEE 802.15.4 stack requires several constants to be defined/adjusted.
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Sergey Lapin <slapin@ossfans.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit f001fde5ea
(net: introduce a list of device addresses dev_addr_list (v6))
added one regression Vegard Nossum found in its testings.
With kmemcheck help, Vegard found some uninitialized memory
was read and reported to user, potentialy leaking kernel data.
( thread can be found on http://lkml.org/lkml/2009/5/30/177 )
dev_addr_init() incorrectly uses sizeof() operator. We were
initializing one byte instead of MAX_ADDR_LEN bytes.
Reported-by: Vegard Nossum <vegard.nossum@gmail.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Neil Horman